The present invention relates to a tape loading device of a magnetic recording/reproducing apparatus such as a cassette type video tape recorder.
As a conventional tape loading device of a cassette type video tape recorder for recording or reproducing a video signal by taking out a magnetic tape from a tape cassette and winding it around the peripheral surface of a rotation drum disposed in the vicinity of the tape cassette, the following type tape loading device is known: A magnetic tape is taken out of the cassette tape using a moving type loading roller post disposed on the supply reel side and winding reel side of a rotation drum and then, the magnetic tape is wound around the rotation drum from both sides thereof.
For example, as shown in FIG. 17, a loading roller post 201 disposed on the winding reel side is moved in the direction shown by the arrow 202 so as to take a magnetic tape 203 out of a tape cassette and at the same time, a loading roller post 204 disposed on the supply reel side is moved in the direction shown by the arrow 205 so as to take the magnetic tape 203 out of the tape cassette. Thereafter, the magnetic tape 203 is wound around a rotation drum 206 from both sides thereof.
However, in order to make the rotation drum compact so that a magnetic recording/reproducing apparatus such as a camera-integrated video tape recorder can be made to be compact, it is necessary to wind the magnetic tape deeply around the rotation drum. To this end, as shown in FIG. 18, the loading roller post 201 disposed on the winding reel side is moved to the back of the rotation drum 206 in the direction shown by the arrow 207. At this time, in order to secure the tape path of the magnetic tape 203, a post 208 is moved in the direction shown by the arrow 209 so as to expand the tape path. The posts 201, 204, and 208 are moved by an appropriate driving means and a loading guide for providing the travel path of the posts 201, 204, and 208, respectively. In FIGS. 17 and 18, reference numeral 210 denotes a fixed type pinch roller. The magnetic tape 203 is sandwiched between the pinch roller 210 and a capstan 212 which moves from the tape cassette side. Thus, the force for driving the magnetic tape 203 is imparted thereto. Reference numeral 213 denotes a device for driving the capstan 212.
In the above known construction, two moving paths are required to move the posts 201 and 208 in the directions shown by the arrows 207 and 209 using each loading guide. Therefore, the spaces for the moving paths are required, which makes it very difficult to make the tape loading device compact. Further, a driving mechanism is necessary for each of the posts 201 and 208, which also makes it difficult to make the device compact.
In order to overcome such a difficulty, it is preferable to provide a construction in which the loading guides denoted by the arrows 207 and 209 are joined with each other to have the same travel path in a certain portion of their movement. But providing a joining portion causes a problem that it is difficult to correctly guide each post 201 and 208 to a predetermined loading terminating position. In order to reduce the size of a tape loading device, it is necessary to reduce the space in which the two posts are moved.
As shown in FIG. 19, a device is known in which the capstan 212 is positioned outside the tape cassette 211 and the pinch roller 210 is moved by the pinch roller arm 215 from the interior of the tape cassette 211 toward the capstan 212 in the direction shown by the arrow 214. According to this construction, the driving device 213 for driving the capstan 212 can be mounted at a position spaced from the tape cassette 211 and similarly to the tape loading devices as shown in FIGS. 17 and 18, the driving device 213 and the tape cassette 211 do not overlap with each other. Thus, the tape loading device as shown in FIG. 19 has an advantage that the thickness thereof in the direction perpendicular to the sheet showing FIG. 19 can be reduced.
Accordingly, the rotation drum 206 can be made to be compact and the thickness of the device can be reduced by adopting a construction which is a combination of the device shown in FIG. 18 and the device shown in FIG. 19. Thus, a compact magnetic recording/reproducing apparatus can be manufactured.
According to such a combination as described above, it may occur that the travel path of the posts 201 and 208 represented by the arrows 207 and 209 in FIG. 18 and the travel path of the pinch roller 210 shown by the arrow 214 in FIG. 19 intersect with each other. When such an intersection occurs, the pinch roller arm 215 and a rail-shaped loading guide for guiding the posts 201 and 208 are likely to interfere with each other before a loading operation is started in the state in which the posts 201 and 208 and the pinch roller 210 are positioned within the tape cassette 211. Therefore, it is necessary to separate the members with a space particularly in the thickness direction of a magnetic recording/reproducing apparatus so as to avoid the occurrence of such an interference, which leads to the increase of the size of the apparatus. This is a main factor for preventing a magnetic recording/reproducing compact apparatus from being manufactured.
Additionally, an annular first driving ring and an annular second driving ring are rotatably held around the rotation drum. The first driving ring is positioned below the second driving ring. The first driving ring and the second driving ring are supported with a certain space provided therebetween by three ring supporting rollers, respectively. A first loading guide guides a first boat of the first loading roller post, and a second loading guide guides a second boat of the second loading roller post. When a first driving gear rotates clockwise, the first driving ring rotates counterclockwise, thus moving the first loading roller post to the loading position along the first loading guide, and the second driving ring rotates clockwise, thus moving the second loading roller post to the loading position along the second loading guide. Thus, the magnetic tape is taken out of the cassette by the loading roller posts, respectively and wound around the rotation drum from both sides thereof.
According to the above construction, the first driving ring and the second driving ring supported by the three ring supporting rollers, respectively cannot be spaced more than a predetermined interval due to the constructions thereof. Therefore, the construction is not suitable for a camera-integrated type VTR which is required to be thin. Since the first and second driving rings are annular, they require the predetermined space corresponding to the width thereof throughout the periphery of the rotation drum. Thus, the construction cannot be made to be less compact than the above interval provided therebetween and moreover, the weight thereof cannot be reduced.